Put the scallions into a bowl of water for 20 minutes to crisp up; drain and set aside.
Cook your noodles according to the package instructions or as follows. Place the noodles in a deep bowl and pour boiling water over them to cover. Let sit for 3 minutes. Drain, rinse, and cut into short lengths (about 2-in/5 cm) with kitchen scissors. Transfer the noodles to a shallow bowl of cold water to cool while you assemble the rest of the salad.
Combine the pepper, carrots, cabbage, fennel, cilantro, and mint in a large bowl. Toss until it looks like pretty confetti. Add the noodles and the reserved scallions, and toss again.
Blend the ginger, lime juice, sriracha, honey, soy sauce, and sesame oil together in a powerful blender or food processor. This makes about ⅔ cup dressing. Spoon 6 tablespoons of the dressing over the veg and noodles. Gently toss with your clean hands until the dressing is well dispersed. Taste and add more dressing or salt, as you desire. Serve with extra dressing, crispy shallots (for a nice crunch and added salt), and chile slices, if desired.